package com.xzjie.gypt.common.utils;

public class MD5Encoder {
	
	private static MD5Encoder md5 = new MD5Encoder();
	
	/*private static final int S11 = 7;

    private static final int S12 = 12;

    private static final int S13 = 17;

    private static final int S14 = 22;

    private static final int S21 = 5;

    private static final int S22 = 9;

    private static final int S23 = 14;

    private static final int S24 = 20;

    private static final int S31 = 4;

    private static final int S32 = 11;

    private static final int S33 = 16;

    private static final int S34 = 23;

    private static final int S41 = 6;

    private static final int S42 = 10;

    private static final int S43 = 15;

    private static final int S44 = 21;*/
    
    private static final byte PADDING[] = { -128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0, 0 };
    
    private long state[];

    private long count[];

    private byte buffer[];

    private String digestHexStr;

    private byte digest[];
    
    public static String getMD5(String var) {
        md5.md5Init();
        md5.md5Update(var.getBytes(), var.length());
        md5.md5Final();
        md5.digestHexStr = "";
        for (int i = 0; i < 16; i++)
            md5.digestHexStr += byteHEX(md5.digest[i]);

        return md5.digestHexStr.toLowerCase();
    }
    
    private MD5Encoder() {
        state = new long[4];
        count = new long[2];
        buffer = new byte[64];
        digest = new byte[16];
        md5Init();
    }
    
    private void md5Init() {
        count[0] = 0L;
        count[1] = 0L;
        state[0] = 0x67452301L;
        state[1] = 0xefcdab89L;
        state[2] = 0x98badcfeL;
        state[3] = 0x10325476L;
    }
    
    private long F(long x, long y, long z) {
        return x & y | ~x & z;
    }

    private long G(long x, long y, long z) {
        return x & z | y & ~z;
    }

    private long H(long x, long y, long z) {
        return x ^ y ^ z;
    }

    private long I(long x, long y, long z) {
        return y ^ (x | ~z);
    }

    private long FF(long a, long b, long c, long d, long x, long s, long ac) {
        a += F(b, c, d) + x + ac;
        a = (int) a << (int) s | (int) a >>> (int) (32L - s);
        a += b;
        return a;
    }

    private long GG(long a, long b, long c, long d, long x, long s, long ac) {
        a += G(b, c, d) + x + ac;
        a = (int) a << (int) s | (int) a >>> (int) (32L - s);
        a += b;
        return a;
    }

    private long HH(long a, long b, long c, long d, long x, long s, long ac) {
        a += H(b, c, d) + x + ac;
        a = (int) a << (int) s | (int) a >>> (int) (32L - s);
        a += b;
        return a;
    }

    private long II(long a, long b, long c, long d, long x, long s, long ac) {
        a += I(b, c, d) + x + ac;
        a = (int) a << (int) s | (int) a >>> (int) (32L - s);
        a += b;
        return a;
    }
    
    private void md5Update(byte inbuf[], int inputLen) {
        byte block[] = new byte[64];
        int index = (int) (count[0] >>> 3) & 0x3f;
        if ((count[0] += inputLen << 3) < (long) (inputLen << 3))
            count[1]++;
        count[1] += inputLen >>> 29;
        int partLen = 64 - index;
        int i;
        if (inputLen >= partLen) {
            md5Memcpy(buffer, inbuf, index, 0, partLen);
            md5Transform(buffer);
            for (i = partLen; i + 63 < inputLen; i += 64) {
                md5Memcpy(block, inbuf, 0, i, 64);
                md5Transform(block);
            }

            index = 0;
        } else {
            i = 0;
        }
        md5Memcpy(buffer, inbuf, index, i, inputLen - i);
    }
    
    private void md5Final() {
        byte bits[] = new byte[8];
        Encode(bits, count, 8);
        int index = (int) (count[0] >>> 3) & 0x3f;
        int padLen = index >= 56 ? 120 - index : 56 - index;
        md5Update(PADDING, padLen);
        md5Update(bits, 8);
        Encode(digest, state, 16);
    }
    
    private void md5Memcpy(byte output[], byte input[], int outpos, int inpos,
            int len) {
        for (int i = 0; i < len; i++)
            output[outpos + i] = input[inpos + i];

    }

    private void md5Transform(byte block[]) {
        long a = state[0];
        long b = state[1];
        long c = state[2];
        long d = state[3];
        long x[] = new long[16];
        Decode(x, block, 64);
        a = FF(a, b, c, d, x[0], 7L, 0xd76aa478L);
        d = FF(d, a, b, c, x[1], 12L, 0xe8c7b756L);
        c = FF(c, d, a, b, x[2], 17L, 0x242070dbL);
        b = FF(b, c, d, a, x[3], 22L, 0xc1bdceeeL);
        a = FF(a, b, c, d, x[4], 7L, 0xf57c0fafL);
        d = FF(d, a, b, c, x[5], 12L, 0x4787c62aL);
        c = FF(c, d, a, b, x[6], 17L, 0xa8304613L);
        b = FF(b, c, d, a, x[7], 22L, 0xfd469501L);
        a = FF(a, b, c, d, x[8], 7L, 0x698098d8L);
        d = FF(d, a, b, c, x[9], 12L, 0x8b44f7afL);
        c = FF(c, d, a, b, x[10], 17L, 0xffff5bb1L);
        b = FF(b, c, d, a, x[11], 22L, 0x895cd7beL);
        a = FF(a, b, c, d, x[12], 7L, 0x6b901122L);
        d = FF(d, a, b, c, x[13], 12L, 0xfd987193L);
        c = FF(c, d, a, b, x[14], 17L, 0xa679438eL);
        b = FF(b, c, d, a, x[15], 22L, 0x49b40821L);
        a = GG(a, b, c, d, x[1], 5L, 0xf61e2562L);
        d = GG(d, a, b, c, x[6], 9L, 0xc040b340L);
        c = GG(c, d, a, b, x[11], 14L, 0x265e5a51L);
        b = GG(b, c, d, a, x[0], 20L, 0xe9b6c7aaL);
        a = GG(a, b, c, d, x[5], 5L, 0xd62f105dL);
        d = GG(d, a, b, c, x[10], 9L, 0x2441453L);
        c = GG(c, d, a, b, x[15], 14L, 0xd8a1e681L);
        b = GG(b, c, d, a, x[4], 20L, 0xe7d3fbc8L);
        a = GG(a, b, c, d, x[9], 5L, 0x21e1cde6L);
        d = GG(d, a, b, c, x[14], 9L, 0xc33707d6L);
        c = GG(c, d, a, b, x[3], 14L, 0xf4d50d87L);
        b = GG(b, c, d, a, x[8], 20L, 0x455a14edL);
        a = GG(a, b, c, d, x[13], 5L, 0xa9e3e905L);
        d = GG(d, a, b, c, x[2], 9L, 0xfcefa3f8L);
        c = GG(c, d, a, b, x[7], 14L, 0x676f02d9L);
        b = GG(b, c, d, a, x[12], 20L, 0x8d2a4c8aL);
        a = HH(a, b, c, d, x[5], 4L, 0xfffa3942L);
        d = HH(d, a, b, c, x[8], 11L, 0x8771f681L);
        c = HH(c, d, a, b, x[11], 16L, 0x6d9d6122L);
        b = HH(b, c, d, a, x[14], 23L, 0xfde5380cL);
        a = HH(a, b, c, d, x[1], 4L, 0xa4beea44L);
        d = HH(d, a, b, c, x[4], 11L, 0x4bdecfa9L);
        c = HH(c, d, a, b, x[7], 16L, 0xf6bb4b60L);
        b = HH(b, c, d, a, x[10], 23L, 0xbebfbc70L);
        a = HH(a, b, c, d, x[13], 4L, 0x289b7ec6L);
        d = HH(d, a, b, c, x[0], 11L, 0xeaa127faL);
        c = HH(c, d, a, b, x[3], 16L, 0xd4ef3085L);
        b = HH(b, c, d, a, x[6], 23L, 0x4881d05L);
        a = HH(a, b, c, d, x[9], 4L, 0xd9d4d039L);
        d = HH(d, a, b, c, x[12], 11L, 0xe6db99e5L);
        c = HH(c, d, a, b, x[15], 16L, 0x1fa27cf8L);
        b = HH(b, c, d, a, x[2], 23L, 0xc4ac5665L);
        a = II(a, b, c, d, x[0], 6L, 0xf4292244L);
        d = II(d, a, b, c, x[7], 10L, 0x432aff97L);
        c = II(c, d, a, b, x[14], 15L, 0xab9423a7L);
        b = II(b, c, d, a, x[5], 21L, 0xfc93a039L);
        a = II(a, b, c, d, x[12], 6L, 0x655b59c3L);
        d = II(d, a, b, c, x[3], 10L, 0x8f0ccc92L);
        c = II(c, d, a, b, x[10], 15L, 0xffeff47dL);
        b = II(b, c, d, a, x[1], 21L, 0x85845dd1L);
        a = II(a, b, c, d, x[8], 6L, 0x6fa87e4fL);
        d = II(d, a, b, c, x[15], 10L, 0xfe2ce6e0L);
        c = II(c, d, a, b, x[6], 15L, 0xa3014314L);
        b = II(b, c, d, a, x[13], 21L, 0x4e0811a1L);
        a = II(a, b, c, d, x[4], 6L, 0xf7537e82L);
        d = II(d, a, b, c, x[11], 10L, 0xbd3af235L);
        c = II(c, d, a, b, x[2], 15L, 0x2ad7d2bbL);
        b = II(b, c, d, a, x[9], 21L, 0xeb86d391L);
        state[0] += a;
        state[1] += b;
        state[2] += c;
        state[3] += d;
    }

    private void Encode(byte output[], long input[], int len) {
        int i = 0;
        for (int j = 0; j < len; j += 4) {
            output[j] = (byte) (int) (input[i] & 255L);
            output[j + 1] = (byte) (int) (input[i] >>> 8 & 255L);
            output[j + 2] = (byte) (int) (input[i] >>> 16 & 255L);
            output[j + 3] = (byte) (int) (input[i] >>> 24 & 255L);
            i++;
        }

    }

    private void Decode(long output[], byte input[], int len) {
        int i = 0;
        for (int j = 0; j < len; j += 4) {
            output[i] = b2iu(input[j]) | b2iu(input[j + 1]) << 8
                    | b2iu(input[j + 2]) << 16 | b2iu(input[j + 3]) << 24;
            i++;
        }

    }

    private static long b2iu(byte b) {
        return (long) (b >= 0 ? b : b & 0xff);
    }

    private static String byteHEX(byte ib) {
        char Digit[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A',
                'B', 'C', 'D', 'E', 'F' };
        char ob[] = new char[2];
        ob[0] = Digit[ib >>> 4 & 0xf];
        ob[1] = Digit[ib & 0xf];
        String s = new String(ob);
        return s;
    }
    
    
    
    
}
